South Portico: A section and axonometric diagram of the South Entrance vestibule after sketches in the HABS field notes for the White House. (White House History Number 29)

South Portico: A section and axonometric diagram of the South Entrance vestibule after sketches in the HABS field notes for the White House. (White House History Number 29)

South Portico: A section and axonometric diagram of the South Entrance vestibule after sketches in the HABS field notes for the White House. The section conveys the irregular nature of the vaulting in this space. Because the top of the groined arches, over the interior and exterior door openings, do not meet the top of the barrel vault at the same height, a true groin vault is not formed. Hoban corrected a difficult situation with masterful adaptation.